Traditionally, only States are considered as duty-bearers under international human rights law. Fundamental human rights guarantees have been conceived as standards of legal protection for individuals against the abuse of States. However, with the emergence of various non-State actors, States are no longer the only entities who may interfere with the enjoyment of human rights. The obligations of certain categories non-State actors under international human rights law have been much studied, but the application of international human rights law to “unrecognised entities”, who fulfil the traditional criteria of statehood and have achieved de facto independence but are not generally recognised as States by the international community, have received relatively limited scholarly attention. This thesis aims to fill this gap and examine whether existing rules of international human rights law, especially those concerning non-State actors, provide any basis for such application. Special emphasis will be placed on the Republic of China (ROC, Taiwan) as an example of an unrecognised entity. From the birth of the United Nations, the ROC government participated in human rights-related work within the organisation. Yet, after the adoption of General Assembly Resolution 2758, which recognised the representatives of the government of the People’s Republic of China as the lawful representatives of China, the ROC’s signatures and ratifications of international treaties are no longer recognised, and Taiwan’s recent attempts to ratify/accede to international human rights treaties have been unsuccessful. Questions arise whether Taiwan is bound by these treaties and non-treaty rules of international human rights law. It is envisaged that an examination of theories and practice regarding the application of international human rights law to unrecognised entities will inform the case study of Taiwan and contribute to the development of arguments justifying the application of international human rights law to Taiwan.